• Proceedings of the Korean Vacuum Society Conference
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• 2004.08a
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• pp.79-79
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• 2004

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.4
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• pp.549-562
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• 2020

Deionized water, methanol, and ethanol were investigated for their effectiveness at dissolving LiCl-KCl-UCl3 at 25, 35, and 50℃ using inductively coupled plasma mass spectrometry (ICP-MS) to study the concentration evolution of uranium and mass ratio evolutions of lithium and potassium in these solvents. A visualization experiment of the dissolution of the ternary salt in solvents was performed at 25℃ for 2 min to gain further understanding of the reactions. Aforementioned solvents were evaluated for their performance on removing the adhered ternary salt from uranium dendrites that were electrochemically separated in a molten LiCl-KCl-UCl3 electrolyte (500℃) using scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Findings indicate that deionized water is best suited for dissolving the ternary salt and removing adhered salt from electrodeposits. The maximum uranium concentrations detected in deionized water, methanol, and ethanol for the different temperature conditions were 8.33, 5.67, 2.79 μg·L-1 for 25℃, 10.62, 5.73, 2.50 μg·L-1 for 35℃, and 11.55, 6.75, and 4.73 μg·L-1 for 50℃. ICP-MS analysis indicates that ethanol did not take up any KCl during dissolutions investigated. SEM-EDS analysis of ethanol washed uranium dendrites confirmed that KCl was still adhered to the surface. Saturation criteria is also proposed and utilized to approximate the state of saturation of the solvents used in the dissolution trials.

• Macromolecular Research
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• v.15 no.1
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• pp.22-30
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• 2007

High water vapor permeable coating materials were prepared by blending aqueous poly(vinyl alcohol) (PVA) solution with waterborne polyurethane-urea (WBPU) dispersions synthesized by prepolymer mixing process. Stable WBPU/PVA dispersions were achieved at PVA content below 30 wt%. As the water soluble polymer PVA content increased, the number and density of total micro-pores (tunnel-like/isolated micro-pores) formed after the dissolution of PVA in water increased, and the water vapor permeability of coated Nylon fabric also increased significantly. Using WBPU/water soluble polymer PVA blends as a coating material and then dissolving PVA in water was confirmed to be an effective method to obtain prominent breathable fabrics.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.71-75
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• 2012

Silk is a natural polymer that has the advantages of the biocompatibility, excellent mechanical strength, low immune rejection, and molding facility. But silk does not dissolve easily in water or general solvent. To investigate the characteristics of silk biological membranes according to dissolving condition of silk fibroin, we made the silk biological membranes using silk fibroin solutions with different amount and dissolving time of silk. The characterizations of the silk biological membranes such as morphology, structure, and mechanical strength were observed. Although each biological membrane has the same fibroin content, there was a significant difference in the thickness and transparency. But there was no significant change in the molecular weight of the silk fibroin solutions and morphology of silk biological membranes. We were established the manufacturing condition for silk fibroin biological membrane. So we expect that the conditions will help in the development of medical supplies in the future.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.778-786
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• 2017

In this study, analyzed the changes occurred after adding casein emulsions to water - dispersed polyurethane using polypropylene glycol (PPG). For this purpose, anionic water - dispersed polyurethane containing PPG, IPDI and DMPA and casein emulsion prepared by dissolving casein in distilled water using ammonia water were prepared. As a result of measuring the alkali resistance by using the prepared resin, there was no change in the physical properties. The tensile strength of the sample having a high casein content was measured to be $2.227kgf/mm^2$. Elongation was measured at 474% for samples containing less casein and The abrasion resistance was measured as 46.090 mg.loss of sample containing much casein as a result of the surface roughness measurement.

• Corrosion Science and Technology
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• v.6 no.3
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• pp.103-111
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• 2007

The effect of stress factors on the growing process of stress corrosion cracking (SCC) of the sensitized 18-8 stainless steel in high temperature water was investigated using equations of crack growth rate derived from applying electric circuits to SCC corrosion paths. Three kinds of cross sections have to be considered when electric circuit is constructed using total current. The first is ion flow passage area, $S_{sol}$, of solution in crack, the second is total dissolving surface area, $S_{dis}$, of metal on electrode of crack tip and the third is dissolving cross section, $S_{met}$, of metal on grain boundary or in base metal or in welding metal. Stress may affect each area. $S_{sol}$ may depend on applied stress, $\sigma_{\infty}$, related with crack depth. $S_{dis}$ is expressed using a factor of $\varepsilon(K)$ and may depend on stress intensity factor, K only. SCC crack growth rate is ordinarily estimated using a variable of K only as stress factor. However it may be expected that SCC crack growth rate depends on both applied stress $\sigma_{\infty}$ and K or both crack depth and K from this consideration.$\varepsilon(K)$ is expressed as ${\varepsilon}(K)=h_2{\cdot}K^2+h_3{\cdot}K^3$ when $h_{2}$ and $h_{3}$ are coefficients. Also, relationships between SCC crack growth rate, da/dt and K were simulated and compared with the literature data of JBWR-VIP-04, NRC NUREG-0313 Rev.2 and SKIFS Draft. It was pointed out in CT test that the difference of distance between a point of application of force and the end of starter notch (starting point of fatigue crack) may be important to estimate SCC crack growth rate. An anode dissolution current density was quantitatively evaluated using a derived equation.

• Membrane and Water Treatment
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• v.13 no.4
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• pp.201-208
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• 2022

Emulsion Liquid Membrane (ELM) is a prominent technique for the separation of heavy metal ions from wastewater due to the fast extraction and is a single-stage operation of stripping-extraction. The selection of the components (Surfactant and Carrier) of ELM is a very significant step for its preparation. In the ELM technique, the primary water- in-oil (W/O) emulsion is emulsified in water to produce water-in-oil-in-water (W/O/W) emulsion. The water in oil emulsion was prepared by mixing the membrane phase and internal phase. To prepare the membrane phase, the extractant D2EHPA (di-2-ethylhexylphosphoric acid) was used as a mobile carrier, Span-80 as a surfactant, and Paraffin as a diluent. Moreover, the internal (receiving) phase was prepared by dissolving sulphuric acid in water. Di-(2- ethylhexyl) phosphoric acid such as surfactant concentration, carrier concentration, sulphuric acid concentration in the receiving (internal) phase, agitation time (emulsion phase and feed phase), the volume ratio of the membrane phase to the receiving phase, the volume ratio of the external feed phase to the primary water-in-oil emulsion and pH of feed were studied on the percentage extraction of metal ions at 20℃. The results show that it is possible to remove 78% for As(V), 98% for Cd(II), and 99% for Pb(II). Emulsion Liquid Membrane (ELM) is a well-known technique for separating heavy metal ions from wastewater due to the fast extraction and is a single-stage operation of stripping-extraction. The selection of ELM components (Surfactant and Carrier) is a very significant step in its preparation. In the ELM technique, the primary water-in-oil (W/O) emulsion is emulsified to produce water-in-oil-in-water (W/O/W) emulsion. The water in the oil emulsion was prepared by mixing the membrane and internal phases. The extractant D2EHPA (di-2-ethylhexylphosphoric acid) was used as a mobile carrier, Span-80 as a surfactant, and Paraffin as a diluent. Moreover, the internal (receiving) phase was prepared by dissolving sulphuric acid in water. Di-(2-ethylhexyl) phosphoric acid such as surfactant concentration, carrier concentration, sulphuric acid concentration in the receiving (internal) phase, agitation time (emulsion phase and feed phase), the volume ratio of the membrane phase to the receiving phase, the volume ratio of the external feed phase to the primary water-in-oil emulsion and pH of feed were studied on the percentage extraction of metal ions at 20℃. The results show that it is possible to remove 78% for As(V), 98% for Cd(II), and 99% for Pb(II).

• Journal of the Korean institute of surface engineering
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• v.52 no.2
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• pp.78-83
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• 2019

Chloride baths for electrodeposited Ni thin films were fabricated by dissolving metal Ni powders with the mixed solution consisting of HCl and de-ionized water. Current efficiency, residual stress, surface morphology and microstructure of Ni films with the change of metal ion ($Ni^{2+}$) concentrations in the plating solution were studied. Current efficiency was measured to be more than 90% with increasing $Ni^{2+}$ concentrations in the plating solution. Residual stress of Ni thin film was increased from about 400 to 780 MPa with increasing $Ni^{2+}$ concentration from 0.2 to 0.5 M. It is gradually decreased to 650 MPa at 0.9 M $Ni^{2+}$ concentration. Smooth surface morphologies were observed over 0.3 M $Ni^{2+}$ concentration, but nodule surface morphology at 0.2 M. Ni films consist of FCC(111), FCC(200), FCC(220) and FCC(311) peaks in XRD patterns. Preferred orientation of FCC(111) was observed and its intensity was slightly decreased with increasing $Ni^{2+}$ concentration. The average grain size was slightly increased at 0.3 M $Ni^{2+}$ concentration and then slightly decreased with increasing $Ni^{2+}$ concentration.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.262-262
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• 2010

We introduce a novel and efficient strategy for producing free-standing functional films via photo-crosslinking and electrostatic layer-by-layer (LbL) assembly, which can allow the buildup of hydrophilic multilayers onto hydrophobic surfaces. Hydrophobic multilayers were deposited on ionic substrates by a photo-crosslinking LbL process using photo-crosslinkable polymers. The photo-crosslinked surface was converted to an anionic surface by excess UV light irradiation. This treatment allowed also the stable adhesion between metal electrode or cationic polyelectrolyte and hydrophobic multilayers. After dissolving the ionic substrates in water, the formed free-standing films exhibited unique functionalities of inserted components within hydrophobic and/or hydrophilic multilayers.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.5
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• pp.24-30
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• 2010

Papermaking technology has drastically improved over the last 20 years to face new challenges. Because environmental regulations have become increasingly strict, papermaking systems have had to accommodate elevated recycled pulp content and an increased use of recycled process water. Process water in papermaking systems has become more dirtier and reduced polymer efficiency. Amphoteric PAM demonstrated a higher degree of stability in a high conductivity environment compared to cationic PAM. This was illustrated by the improved retention performance, particularly the ash retention. This amphoteric polymer can be used for board or newsprint production using recycled pulp, especially for the systems where polymer dissolving water is high in conductivity and degradation of cationic functional groups of cationic PAM can occur.